Before buying a bidet seat, you’ll need to know what kind of shape and size your toilet is. Is it elongated or round? Is it one piece or two? Most bidets are made to fit one standard type of toilet and won’t slot properly into others. If you bought a toilet seat bidet and couldn’t get it set up despite following installation instructions, chances are, you’ve bought the wrong size of seat.

In case you can’t tell your type of toilet just by looking at it, try and find the old packaging the seat was on (if you still have it) as the type will usually be printed on there. As a last resort, you can haul the toilet seat down with you to the hardware store and ask the store clerks for help while buying a new bidet.

If carrying a use toilet seat around isn’t your cup of tea, you can also opt to get a universal-sized bidet. Personally, I don’t think it’s the best seat anyone can get for their toilets (exact fit is always better), but it will do.

Universal bidets are also good if you have an irregularly-shaped toilet installed in your bathroom or if you’re planning to move anytime soon. Since you have little control as to what kind of toilets are installed in your next home, a universal bidet seat should prove a better investment.